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Reading this answer about GA aircraft ditching, I wondered if, considering conventional fixed landing gear aircraft (taildraggers) which often operate overwater, having the ability to jettison the landing gear before ditching would increase safety by reducing chances of flipping inverted when wheels contact water?

Regardless of how this mechanism would work, explosive bolts or manual release mechanism, would this added complexity/weight be practical considering ditching probabilities, and are there been studies about this?

Here's a video showing one Cessna with retractable landing gear, ditching gear up, avoiding it to flip inverted.

https://www.youtube.com/embed/8rr2ZjGbdAA?start=23&end=33

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    $\begingroup$ "would this added complexity/weight be practical considering ditching probabilities" Most likely "No", which is why it hasn't been implemented. $\endgroup$
    – FreeMan
    May 14, 2020 at 11:23
  • $\begingroup$ Such mechanisms used to exist: "Some aircraft use wheels for takeoff and jettison them when airborne for improved streamlining without the complexity, weight and space requirements of a retraction mechanism." (Detachable Landing Gear). But that was for regular use, not for ditching... $\endgroup$
    – Bianfable
    May 14, 2020 at 11:26
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    $\begingroup$ It was also done with this aircraft, both to improve range and to increase safety in case of ditching -- en.wikipedia.org/wiki/L%27Oiseau_Blanc $\endgroup$
    – quiet flyer
    May 14, 2020 at 12:30
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    $\begingroup$ @quietflyer your comment should be an answer. $\endgroup$
    – Joooeey
    May 14, 2020 at 19:34

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According to at least one source (based on NTSB data) there were 179 registered ditchings of GA aircraft over a period of 8 years, or an average of approx 22 per year. The trend however were going downwards from 30 in the mid-80s to 12-15 ditchings in the mid-90s when the study ended.

In all 22 fatalities were registered, with an 88% overall survival rate but a 92% egress rate. The egress rate is what is important for your question. Discard the long-range ocean-ferry flights and this number rises to 95%.

It's worth mentioning that there numbers are for registered ditchings. Unregistered ditchings are more likely to be successful than not, so the real survival rate is likely to be higher.

According to the report:

"Where and when you ditch matters more than what you ditch. Examining the fatal accidents, we found that two-thirds of the 22 occurred during the winter in cold or temperate climates and 12 percent are what we call "blue water" ditchings in the open Atlantic or Pacific, done by ferry pilots on extraordinary missions in light singles or twins, or fish spotters operating far from shore."

If you want to have a landing gear that can be jettisoned, chances are that it would add quite a bit of complexity and maintenance to address a non-problem. 9 of the 22 fatalities involved an aircraft with retractable landing gear, but the study makes it clear that the status of the landing gear was unknown, so we don't know if or how this affected the statistics.

The problem isn't ditching with or without a landing gear, it's the fact that you're ditching in the first place. And when it happens it most likely does so without you having appropriate survival gear.

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    $\begingroup$ Really good answer @bjelleklang, I would forsee far more mayhem from release mechanism failures causing an emergency. In any case we don't know how many fatalities would have been averted with such a system, and no way to quantify them. Even if we assume the 13 fatalities of fixed gear ditchings were due to flipping (and that's a bad assumption) it wouldn't be worth it. $\endgroup$
    – GdD
    May 14, 2020 at 12:43
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    $\begingroup$ @bjelleklang the only thing I would add is that the most important component to surviving a ditching and egressing successfully is having a shoulder harness and using it. $\endgroup$
    – John K
    May 14, 2020 at 12:49
  • $\begingroup$ @GdD: Thanks. I suspect that we'd see more accidents as a result of landing gears being jettisoned as well. And the last thing you want is a jettison mechanism failing just when you're trying to land normally, or when you are in distress trying to get rid of the gear. $\endgroup$
    – bjelleklang
    May 14, 2020 at 20:08
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    $\begingroup$ @JohnK: Absolutely. What equipment you bring seems to be more important than what aircraft you fly according to the study, so as far as I can tell there is no real difference between fixed or retractable gear, or high versus low-winged airplanes. $\endgroup$
    – bjelleklang
    May 14, 2020 at 20:08
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    $\begingroup$ Another interesting number would be the number of ditching vs. the number of landings in the same period, and how reliable the mechanism would need to be to not create more accidents by uncommanded or accidental deployment of the mechanism or undesired failure of the detachment point leading to gear-up landings or collapsing gear during landing. $\endgroup$
    – Jörg W Mittag
    May 15, 2020 at 6:11

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